-The VUV spectra of solids are often dominated by7 atomic or molecular effects, which clearly manifest themselves in the gross features of the spectra and the fine structllre at inner shell excjtation thresholds. Evideng for the influence of atomic and molecular matrlx elements, multiplet-splitting and correlation is presented. Special emphasis is given to the direct experimental verification b...

Using a beam-gas arrangement, we have obtained the chemiluminescence spectra of alkali-halogen reactions at pressures less than I mtorr. The spectra in general are characterized by a broad molecular feature on which are superimposed sharp atomic alkali transitions. Under higher resolution (better than 5 A) the molecular feature consists of a single progression of regularly spaced peaks extendin...

The following work is devoted to the description of atoms and ions in strong magnetic fields as they can occur in the vicinity of magnetic white dwarfs and neutron stars. The ultimate goal of this work is the contribution to an understanding of unique absorption features detected in the spectra of such stars. One natural explanation for these features are atomic absorptions in the stars’ strong...

X-ray absorption spectroscopy and vacuum ultra-violet spectroscopic ellipsometry are used to study the electronic structure of complex oxides comprised of mixed TM/TM and TM/RE oxides. Experimental spectra for HfTiO4 and Gd(Dy)ScO3 indicate multiple d-state features in the O K1 edge. These are compared with the empirical models for atomic d-state mixing. It is concluded that a mean field, virtu...

We describe the operation of two GaN-based diode lasers for the laser spectroscopy of gallium at 403 nm and 417 nm. Their use in an external cavity configuration enabled the investigation of absorption spectroscopy in a gallium hollow cathode. We have analyzed the Doppler broadened profiles accounting for hyperfine and isotope structure and extracting both the temperature and densities of the n...

Laser-driven rescattering of electrons is the basis of many strong-field phenomena in atoms and molecules. Here, we will show how this mechanism operates in extended atomic systems, giving rise to effective energy absorption. Rescattering from extended systems can also lead to energy loss, which in its extreme form results in non-linear photo-association. Intense-laser interaction with atomic c...

We study several effects that influence the strength of the proton cyclotron and atomic features in the thermal spectra of magnetic neutron stars. Magnetic field variations over the neutron star surface leads to broadening of features. Vacuum polarization can strongly suppress spectral lines when B >∼ 10 G. The surface spectrum is unaffected by vacuum polarization when B <∼ 7× 10 G; thus the pr...

introduction: recent investigations have detected the presence of significant levels of heavy metals (chromium, lead and cadmium) in toys and other pvc products manufactured for children. in some countries, addition of compounds containing toxic metals to toys are limited or prohibited. methods: to evaluate the safety of some of the plastic toys in the city of isfahan with respect to toxic trac...

an efficient, rapid, simple, and highly selective dispersive liquid–liquid microextraction basedon solidification of floating organic drop (dllme-sfod), combined with flame atomicabsorption spectrometry was developed for preconcentration and determination of trace amountsof cobalt in water samples. in this method, an appropriate mixture of acetone and1-undecanol was injected rapidly into the aq...

current study was done to determine the concentration of heavy metals including lead and cadmium and nutrients element copper and zinc in a simple and whole wheat macaroni in the valid different supermarkets in the city of tehran. 254 samples from seven iranian simple macaroni , four foreign simple macaroni and two iranian whole wheat macaroni were purchased consecutively in 3 seasons of 2015. ...